Profit split method selection requires adequate transfer pricing data; reasons must be recorded if PSM cannot be applied before using alternatives. PSM is suited for transfer of unique intangibles or interrelated transactions and allocates returns based on relative contributions; cost based methods tied to R&D costs are generally discouraged. Application of PSM depends on transaction nature, functions, assets, risks, and critically on availability, coverage and reliability of data. If a Transfer Pricing Officer concludes PSM cannot be applied due to data deficiencies, the officer must record reasons for non applicability before considering TNMM or CUP, and taxpayers are required to maintain prescribed documentation, so lack of information requires good and sufficient reason.